I don't know if we have any 501st Legion members here. Our members tend to go towards the Mando Mercs generally because after making Mando armour it's a lot easier to just sign up another set with them than go to the 501st. Also, the 501st only allow cannon characters while the Mercs almost encourage individuality.

Anyway, I'm not the one to talk to on such matters. Mereel Skirata, Dha'Werd Krayt, etc. are better suited at this stuff than I.